1. Field of the Invention
This invention relates generally to semiconductor fabrication technology, and, more particularly, to efficiently storing data relating to semiconductor fabrication processes.
2. Description of the Related Art
There is a constant drive within the semiconductor industry to increase the quality, reliability and throughput of integrated circuit devices, e.g., microprocessors, memory devices, and the like. This drive is fueled by consumer demands for higher quality computers and electronic devices that operate more reliably. These demands have resulted in a continual improvement in the manufacture of semiconductor devices, e.g., transistors, as well as in the manufacture of integrated circuit devices incorporating such transistors. Additionally, reducing defects in the manufacture of the components of a typical transistor also lowers the overall cost per transistor as well as the cost of integrated circuit devices incorporating such transistors.
The technologies underlying semiconductor processing tools have attracted increased attention over the last several years, resulting in substantial refinements. However, despite the advances made in this area, many of the processing tools that are currently commercially available suffer certain deficiencies. In particular, such tools often lack advanced process data monitoring capabilities, such as the ability to provide historical parametric data in a user-friendly format, as well as event logging, real-time graphical display of both current processing parameters and the processing parameters of the entire run, and remote, i.e., local site and worldwide, monitoring. These deficiencies can engender nonoptimal control of critical processing parameters, such as throughput accuracy, stability and repeatability, processing temperatures, mechanical tool parameters, and the like. This variability manifests itself as within-run disparities, run-to-run disparities and tool-to-tool disparities that can propagate into deviations in product quality and performance.
An additional set of problems is posed by the sheer amount of processing data available to monitor. For example, in monitoring an etching process using optical emission spectroscopy (OES), problems are posed by the sheer number of OES frequencies or wavelengths available to monitor. The monitoring and/or control of each of the many processing steps in a wafer fabrication facility typically generates a large amount of processing data. For example, a data file for each wafer monitored, in an etching process using optical emission spectroscopy (OES), may be as large as 2-3 megabytes (MB), and each etcher can typically process about 500-700 wafers per day. Conventional storage methods would require over a gigabyte (GB) of storage space per etcher per day and over 365 GB per etcher per year. Further, the raw OES data generated in such monitoring is typically xe2x80x9cnoisyxe2x80x9d and unenhanced.
The present invention is directed to overcoming, or at least reducing the effects of, one or more of the problems set forth above.
In one aspect of the present invention, a method is provided for compressing data. The method comprises collecting processing data representative of a process. The method further comprises modeling the collected processing data using a control model. The method also comprises applying the control model to compress the collected processing data.
In another aspect of the present invention, a computer-readable, program storage device is provided, encoded with instructions that, when executed by a computer, perform a method, the method comprising collecting processing data representative of a process. The method further comprises modeling the collected processing data using a control model. The method also comprises applying the control model to compress the collected processing data.
In yet another aspect of the present invention, a computer programmed to perform a method is provided, the method comprising collecting processing data representative of a process. The method further comprises modeling the collected processing data using a control model. The method also comprises applying the control model to compress the collected processing data.